# Help! Solving simultaneous equations using the graph method

• Jan 27th 2009, 04:14 AM
IPFreely
Help! Solving simultaneous equations using the graph method
Hi all, I would be very grateful if someone could assist me with solving simultaneous equations using the graph method.

Here is the question:
Robot A follows a route which has the equation y = x - 2 and Robot B follows a route which has the equation 2y = x + 7. Find the co-ordinates that both robots pass over by plotting the two routes.

• Jan 27th 2009, 05:00 AM
Quote:

Originally Posted by IPFreely
Hi all, I would be very grateful if someone could assist me with solving simultaneous equations using the graph method.

Here is the question:
Robot A follows a route which has the equation y = x - 2 and Robot B follows a route which has the equation 2y = x + 7. Find the co-ordinates that both robots pass over by plotting the two routes.

(Hi)On the graph do the following
-take one value of x , find the corresponding value of y in the first equation ,(x,y) is one point on that path

-Repeat above steps three times and join( and extend) the three points this is the first path

-Do the same thing for next equation(Happy) and march ahead
• Jan 27th 2009, 08:31 AM
darkness9375
Quote:

Originally Posted by IPFreely
Hi all, I would be very grateful if someone could assist me with solving simultaneous equations using the graph method.

Here is the question:
Robot A follows a route which has the equation y = x - 2 and Robot B follows a route which has the equation 2y = x + 7. Find the co-ordinates that both robots pass over by plotting the two routes.

well as you know we have to line then up.
so....

y=x-2..... (we have to bring numbers to one side and the un-known's to 2y=x+7 the other)

y-x=-2
2y-x=7..... we have to change the signs so the x's well cancel

-y+x=2
2y-x=7 as you can see the x's well go

y=9

now you fill in for y.

y=x-2
9=x-2
9+2=x
11=x

do you understand it? any questions just ask(Wink)